Police officials said the deadliest of the attacks took place at night when a car bomb exploded near a market in Baghdad's northeastern district of Shaab, killing 10 people, including three policemen, and wounding 13 others. (Agencies)
A car bomb also exploded in a commercial street in northwestern Baghdad, police said, killing five people and wounding 14.
Another car bomb killed four and wounded 12 in a commercial street in Baghdad's Hurriyah neighbourhood, police said. Earlier, another car bomb exploded in a commercial street in northern Baghdad, killing three people and wounding 13 others.
Near the city of Fallujah, army artillery shelled a village overnight, killing four civilians, hospital officials said.
Medics in nearby hospital confirmed the death toll for all attacks. All officials spoke on condition of anonymity because they weren't authorized to release the information.
Meanwhile, the UN chief Ban Ki-moon arrived in Baghdad on a visit aimed at discussing regional issues, especially the crisis in Syria. Ban expressed deep concern over the violence hitting Iraq's Sunni-dominated Anbar province.
"The situation in Anbar Governorate, particularly in Fallujah and Ramadi, is a source of grave concern. The security situation in Iraq is undoubtedly a source of great concern," he told reporters during a joint press conference with the Iraqi Prime Minister Nouri al-Maliki.
Iraqi security forces and allied Sunni tribesmen in Anbar have been battling Al-Qaeda fighters from the Islamic State in Iraq and the Levant but have yet to recapture the city of Fallujah or parts of the provincial capital, Ramadi.
The extremist militants, emboldened by fellow fighters' gains in the war in neighbouring Syria, have tried to position themselves as the champions of Iraqi Sunnis angry at the Shiite-led government over what they see as efforts to marginalize them.
Police officials said the deadliest of the attacks took place at night when a car bomb exploded near a market in Baghdad's northeastern district of Shaab, killing 10 people, including three policemen, and wounding 13 others.